Dispelling nutrition myths, ranting, and occasionally, raving


4 Comments

Do 6 amazing body changes really occur when you give-up carbs?

download

This article is nearly two years old now but given that I just saw it shared on social media recently, and the number of evangelical LCHF preachers around, I think it’s worth talking about.

Can we start by discussing that headline? 6 Amazing Body Changes When You Give Up Carbs. Stated as if magical things will occur in your cells, transforming you into a superhuman. Stated as if it’s a given that giving up carbs is the miracle cure for the imperfect vessel of flesh in which you reside. Stated as if these six amazing changes are guaranteed to occur no matter who you are.

So, what are these six amazing changes?

  1. When You Give Up Carbs…You Start Burning Fat

This is not necessarily true. It depends on what you replace the carbs in your diet with. If you replace the carbs in your diet with protein, you’ll burn protein. If you replace the carbs in your diet with fat, you’ll burn fat. If you create a caloric deficit by giving up carbs then you’ll burn fat and probably muscle because you’ll need to get energy to function from somewhere.

2. When You Give Up Carbs…You Feel Less Hungry

If you are creating a caloric deficit by giving up carbs then, sorry, you are going to feel hungry. Reducing your food intake does not immediately result in a reduction in hunger. However, if you are able to maintain a low carb diet and enter into ketosis there is some research that shows you may experience some suppression of appetite.

3. When You Give Up Carbs…Your Belly Gets Flatter

Here the author is stating that your belly will become flatter if you replace simple carbs with high-fibre foods. This is not really a benefit of a low-carb diet, but a benefit of increased fibre intake (and their suggestion to swap white bread for whole grain is certainly not low-carb). However, for many people, increasing fibre can lead to gas and bloating, having the opposite effect of that claimed by the author. That being said, most people should consume more fibre, being sure to increase consumption gradually along with plenty of fluids to avoid blockages. With time, your body will adjust to increased fibre intake.

4. When You Give Up Carbs…You Slash Your Risk of Diabetes

To date, there is no research to support this. While a low-carb diet may help some people with type 2 diabetes control their blood sugar, it doesn’t necessarily work for everyone and there is no data to show that a low-carb diet will prevent diabetes. A balanced diet with plenty of vegetables and regular exercise and physical activity are the best ways to prevent type 2 diabetes. There is no need to go to the extreme and cut out carbs to prevent disease. Also, depending what those carbs are replaced with, you may end-up increasing your risk of developing other chronic diseases.

5. When You Give Up Carbs…Your Muscles Get Stronger

This would only be the case if you were consuming insufficient protein (extremely uncommon in the Western world) before embarking on a low-carb diet. If you are consuming adequate protein, adding more protein will be of no benefit to your muscles. Also, without working your muscles they’re not going to get bigger. You can’t just sit around drinking protein shakes all day and expect to get swole.

6. When You Give Up Carbs…You Feel More Energized

Not all carbs are bad, of course. Your body needs carbohydrates to function properly, and they’re especially important for adequate brain and muscle function. By switching from simple carbs to more long-running fuel—fruits and vegetables, whole-wheat bread, oatmeal, brown rice, quinoa and other whole-grain options—you’ll ensure you have a steady flow of energy and avoid the ups and downs that simple carbs cause.

Way to stick this in the last bullet and undermine the entire premise of the article. This is not a benefit of a low-carb diet. If you are switching from refined simple carbs to complex carbs and whole grains you are simply following that lame old unsexy advice that we dietitians have been repeating for decades.

Let’s not even get into the fact that whole wheat bread has pretty much the same glycemic load as white bread per serving.

I think the author also missed a few other “amazing body changes” that happen when you “give-up” carbs such as, fatigue (which generally goes away after a few days or weeks), flatulence, bad breath, and irritability.

What it comes down to, is that the author is conflating low-carb diets with low-simple carb diets and mixing the claims about the two diets together in this list.

While some people can live happily and healthily on low-carb diets, most people can live (likely more) happily and just as healthily on diets that are not low in carbs.

 

Advertisements


34 Comments

Insane in the Grain Brain

url

My library hold finally came in! No way was I paying to read Grain Brain. I like to financially support quacks as little as possible.

First thought: Including a quote from Dr. Oz on the front cover of your book does little for your credibility.

Second thought: I really like the font used for the Contents page.

Introduction“I’m also a founding member and fellow of the American Board of Integrative and Holistic Medicine.” Cue alarm bells! He said the “H-word”! I promptly googled the organization to learn more. Hmm… While I like the general notion of treating the patient as a whole I’m not sure about this principle: “Integrative holistic physicians strive to relate to patients with grace, kindness and acceptance, emanating from the attitude of unconditional love as life’s most powerful healer.” Love as the most powerful healer?? Call me crazy but I’m not going to my doc for love to heal me when I have an injury or infection. For more about the ABIH check out this post on Science-Based Medicine. Which confirms my fear that this certification has essentially zero meaning. Okay… So the author, David Perlmutter, is the founder of a quack organization. Still, just for fun, I’ll keep reading and see what his “proof” regarding the toxicity of grains is.

Modern wheat is not the same as the wheat of our ancestors. Yeah, yeah. We’ve heard this all before.

“Why is precious little information made available about how we can keep our brains healthy and stave off brain diseases?” I do like this question. Also, I suspect the answer is the same for the brain as for other organs: get plenty of exercise, avoid being sedentary, cook for yourself, and eat more veg. Oh, wait. Not according to Perlmutter, “it’s pointless to consume antioxidants.” Forget the veg, apparently we should all be eating more fat and cholesterol.

Self-Assessment: Ooh! This should be fun! I got 7 out of 20. Zero is optimal but at least I’m not in the “hazard zone” which is anything over 10.

Chapter 1“As many as 40 percent of us can’t properly process gluten”. Reference please. Where did this figure come from and what precisely does inability to properly process gluten mean?

Yes, cholesterol is essential in our bodies. However, a dietary source of cholesterol is not essential. Our bodies can make it. Also, what does this have to do with grains being the cause of brain degeneration and diseases?

Chapter 2: I wonder what this “test for gluten sensitivity” he’s ordering for his patients is. I can’t dispute these tales of improvement in patients following elimination of gluten. However, it’s important to note that we don’t have all of the details and elimination of gluten may not have been the “cure” for migraines and bipolar disorder Perlmutter wants us to believe it is.

A lovely image of a brain scan of a “gluten sensitive” patient versus one of a “normal” patient shows extensive damage in the GS brain. Obviously, this is proof that gluten causes brain damage. Or is it? Remember, correlation does not equal causation. And one brain scan image does not mean gluten will destroy your brain.

In the chapter about gluten Perlmutter says, “one of the main reasons why consuming so many grains and carbs can be so harmful is that they raise blood sugar”. Huh? So the cause of brain disorders is gluten, which is a protein, which would not impact blood sugar. So why are we now talking about carbs?

Chapter 3: “I’ll explain why consuming excess carbohydrates – even those that don’t contain gluten – can be just as harmful as eating a gluten-laden diet.” Sigh. Carbs are evil, fat is good. This is just Wheat Belly redux. Also, while I’m in agreement that all fats (with the exception of man-made trans-fats) can be part of a healthy diet and some of us need more (or less) than others, I think we also need to remember that fats contain more calories per gram than other macronutrients. Thus, if weight control is a concern, we must be careful not to consume overly large portions of calorie-dense high-fat foods.

Perlmutter argues that elevated cholesterol is not only not a risk factor for cardiovascular disease, it’s actually protective against CVD, ALS, and other diseases. The primary basis for this claim was a large study in Norway. The researchers found that there was a U-shaped association between total cholesterol and mortality from CVD. This would suggest that cholesterol has an optimal level (between 5.0 and 7.0 mmol L -1). People below 5.0, or at 7.0 or above, were more likely to die from CVD during the course of the study. Interesting indeed. However, those who had CVD at the start of the study were excluded and the researchers didn’t look at the difference between HDL and LDL profiles. I can’t help but wonder if examining these things would have made any difference to the findings. Even assuming their findings are accurate, they still don’t suggest that high levels of serum cholesterol are protective. They merely suggest that both high and low cholesterol may be associated with CVD.

Perlmutter moves on to argue that the use of statins increases the risk of developing Type 2 Diabetes (remind me again how this pertains to grains and gluten being toxic?). He cites a 2012 study that found a 48% increased risk of developing diabetes for women who took statin medications in contrast to women who did not. That sounds huge but it’s actually not as big as it sounds; 9.93% of statin users were diagnosed with DM2 versus 6.41% of non-statin users. This was also an observational study so causal claims cannot be made. While researchers did control for some confounders it’s entirely possible that there was another reason for the relatively greater risk experienced by the statin users, like, oh, say elevated LDL or another related health condition. There was also a large difference in the sample sizes for each group (10, 834 statin users and 143, 006 non-statin users) which makes me leery about drawing precise comparisons.

Chapter 4: Near the end of this chapter Perlmutter cites a 2012 study of weight loss maintenance (he fails to make the maintenance part very clear) as proof positive that a low-carb, high-fat diet is “the best diet for maintaining weight loss.” To be clear, the study had participants lose weight and then put them on one of three possible weight-loss maintenance diets for 4 weeks. They did find that the low-carb diet “produced the greatest improvements in most metabolic syndrome components examined herein” with a couple of caveats: 1. participants also experienced elevated urinary cortisol excretion 2. C-reative protein was found to be higher in this group. So, while some areas, such as resting metabolic rate, were better for participants on this diet, there were also negative effects. In addition, it’s important to note that the sample size was very small, only 21 people. Also, four weeks is not the same as a lifetime. It’s impossible to extrapolate from this experiment that a low-carb, high-fat diet is the optimal diet for health. Nor can we tell if it’s a realistic diet. Even if it does prove to be optimal for health it doesn’t really matter if nearly no one finds it possible to adhere to. I think that Perlmutter is taking it a little too far (yes, I’m being kind) to draw the conclusion that we should all switch from carbs to fats on the basis of this study.

Chapter 5: Perlmutter is making the argument for neurogenesis and discussing the benefits of exercise (I fully support this) as well as caloric restriction (I think the jury’s still out on this one). I do find it interesting that he’s advocating for a high-fat, low-calorie diet. I would think that this would be very difficult to follow; eating small amounts (Perlmutter recommends reducing caloric intake by 30%) of calorie-dense foods likely wouldn’t be very satiating. Just me speculating though.

I can’t help but think that Perlmutter is cherry picking research that supports his hypothesis. Grain Brain reminds me of how I used to write research papers in high school. I would develop an outline, start writing, and find sources that supported my hypothesis to use as citations.

Chapter 6: In this chapter, Perlmutter discusses the possible connection between gluten sensitivity and various mental illnesses; including: depression, autism, tourette’s, and ADHD. Complete with compelling tales of curing patients by placing them on gluten-free diets. While there may be some connection to gluten sensitivity in some of these illnesses (a recent study found a correlation between autism spectrum disorders and positive serologic celiac disease – but not for gut mucosa – test results) I think that without the corresponding evidence that Perlmutter is providing many individuals with false hope. Anecdotal evidence is not the same as scientific evidence and it’s important to note that, in most cases, no link (correlational or causal) has been drawn between gluten and mental illness. That’s not to say that gluten-elimination isn’t worth trying but in the majority of cases it’s unlikely to alleviate symptoms.

I’m reading about how a study of children with celiac disease found an increased risk of headaches of 833% in comparison to the general population. I decided to take a look at the original research Perlmutter cited with the hope of going on a little rant about relative risk (after all, it was 5% of the children in the study with celiac disease who experienced “headache”, versus 0.6% in the general population, still a small minority of children). However, the article that I found that matches the citation by Perlmutter doesn’t contain any such information. In fact, it contains zero mention of celiac disease or gluten whatsoever. Perhaps the citation is mismatched? (Let’s give Perlmutter the benefit of the doubt here). Regardless, it makes it that much more difficult to dispute (or support) his claims when the claims and the citations don’t correspond.

Chapter 7: In this chapter Permutter states, ” many of today’s physicians… don’t have a firm grasp of nutrition and its effects upon your health.” Hear hear! Cue the opportunity to promote the services of registered dietitians. Oh, wait. Perlmutter simply says that he hopes this will change with the next generation of doctors. Sigh. He then goes on to list a number of supplements that apparently we should all be taking.

DHA – Yes, along with EPA in fish oil, this may provide some neurological and cardiovascular benefits (1). Resveratrol – The jury’s still out on this one but more recent research has put a damper on earlier studies praising it as a life-extender (2). Turmeric – This spice is still being researched, and while promising, no conclusions have been reached regarding its benefits. The study Perlmutter cites was epidemiological research which asked residents of Singapore how often they ate curry. Those who ate curry occasionally, often, or very often, performed better on a test of cognitive ability. Of course, there’s potential for missed confounding variables, as well as the possibility that the difference could be attributed to some other component of curry. Probiotics – Again, we are still in the early stages of research linking gut microbiota and brain health. Perlmutter advises against consuming some probiotic foods as they often come with too much sugar. Instead he suggests taking a supplement. As a dietitian, I always think that it’s best to obtain your nutrients from foods whenever possible. Add foods like plain yoghurt, kefir, sauerkraut, miso, and kimchi to your diet to obtain probiotics. Coconut oil – There is some interesting research underway investigating the effects of coconut oil on Alzheimer’s patients (3). I certainly think that it’s a good idea to incorporate a variety of fats in our diets. However, I don’t think that we should go overboard with any one food. Alpha-lipoic Acid – May have some neurological benefits but the research thus far is not strong (4). Vitamin D – It seems like for every positive study regarding vitamin D there’s another study claiming that it’s useless, or even harmful. In our Northern climate, until research shows otherwise, it is still prudent to supplement with Vitamin D during the winter months.

Chapter 8: Shocker: I wholeheartedly agree with everything Perlmutter has to say in this chapter. He is emphasizing the importance of exercise for brain health. Nothing about grains or carbs.

Chapter 9: Another chapter without mention of grains and carbs. Another chapter I actually agree with Perlmutter. Sleep is vitally important for health.

Chapter 10: We’re just getting into general healthy living tips now and recommendations for how to implement the Grain Brain diet. Most of them are perfectly reasonable. Following this, there are some recipes.

As I sat eating birthday cake (it’s birthday season in my family) and contemplating how to conclude this post I commented to my boyfriend, “Who knows, maybe eating cake will give me Alzheimer’s one day.” Considering how few people develop Alzheimer’s disease (14.9% of Canadians over 65 have some form of dementia) and how many people consume grains (statistics unavailable but I’m assuming it’s roughly 100%) based on the current lack of robust evidence it’s a risk I’m willing to take. I hope to celebrate my birthday tomorrow with some cake.


1 Comment

For the love of carbs

I recently made the error of engaging in a “discussion” about carbs with a personal trainer. I tried to bite my tongue, really I did! This trainer was advising someone about nutrition and told them that carbs are only needed for recovery post-workout and energy pre-workout; fat and protein are the only essential macronutrients. The logic was that fats and proteins can be turned into glucose but we can’t synthesize amino acids and fatty acids from glucose. And, apparently, the proof lies in the traditional Inuit diet which consisted solely of animal products.

Perhaps there is a lesson here that more people can benefit from. On the off chance that there is, I thought that I would share my thoughts with you too. First, the Inuit diet is not a great example as they also consumed berries, wild plants, and seaweed, basically any plants that were available to them. Also, glucose is not the only nutrient at play when we’re talking about carbohydrates. Carbohydrates are also not just in our diet as processed grains and sugar. Fruits and vegetables provide us with carbohydrates as well as fibre, vitamins, and minerals. We need to be careful tossing around the word “carbs” because it can lead people to believe that any food with “carbs” is “evil” and perhaps not just the processed white breads and baked goods that are intended to be demonized (which are still okay as occasional treats). Carbohydrates provide our bodies (including our cells and muscles) with energy. They are also the fuel for our brains. Fibre aids in digestion, weight maintenance, regularity, and can help protect against chronic diseases. Carbs are essential to our health and it’s recommended that 45-60% of our total energy intake come from carbs. The key lies in choosing the right kind of carbs. That means selecting complex carbohydrate foods that are high in fibre and other nutrients and avoiding/limiting highly processed simple carbs. Choose things like fruits and vegetables and whole grains.


2 Comments

The truth about carb cutting

Myth 2: Avoid carbs if you want to lose weight.
What Dietitians of Canada says:
“Cutting carbohydrates (carbs) may help you lose weight in the short term, but it’s mostly because you are eating less food and fewer calories. Drastically cutting carbs means you’ll miss out on the nutritional benefits of healthy choices like whole grains, fruit, starchy vegetables, and legumes. Because so many foods are off-limits, it can be tough to stick with low-carb diets for very long. The best weight-loss plan is one you can stick with. To lose weight and keep it off, exercise regularly and use Canada’s Food Guide to plan a balanced diet with good food choices in the right amounts for you.”
What I say:
Cutting carbs will help you lose weight. However, it’s not a sensible healthy way to do it. Cutting carbs can lead to dangerous and/or simply undesirable side-effects such as ketosis, bad breath, constipation, headaches, and dehydration. We know that low-carb diets produce weight loss in the short-term. However, they’re not sustainable. Your brain, in particular, needs glucose to function, which it doesn’t receive when you’re eating a carb-free diet. Also, it’s incredibly difficult to maintain such a limiting diet and once you go off it you’re likely to gain all the weight you lost back, if not more. It’s not fast or trendy but the best way to lose weight is to make sustainable healthy choices. Make healthy eating and lifestyle choices that you’re willing to continue for the rest of your life and it’s more likely that life will be a long and healthy one.